We're all familiar with Pussy's appearance in the mirror in the episode "Proshai, Livushka" at Livia's wake. But a few minutes later in that same scene, when Janice calls everyone into the living room for a remembrance of Livia, while she is playing Livia's favorite song, you can see a man walk half way down the stairs, stop for a moment, and then walk back upstairs.

My dad thinks it was just someone who was hanging out upstairs, heard the music, came down to see what was going on, and then went back upstairs, not wanting to have any part in the silly gathering. But nobody would just wander around someone's upstairs by themselves. It's just not polite.

So, is it a ghost? Maybe Tony's father making sure his wife is dead?